Fixation clamp with spacer

ABSTRACT

A clamping device of an external fixation system that has a jaw set with a passage at one end configured to hold an element from a first range of sizes and a second passage configured to hold an element from a different range of sizes. The jaw set includes a first jaw, a second jaw, and a slider interposed between the first and second jaws that moves to a first position when the first element is located in the first passage and to a second position when the second element is located in the second passage.

PRIORITY

The present disclosure claims priority to and the benefit of the filingdate of U.S. Provisional Patent Application 62/689,437, filed Jun. 25,2018 and U.S. Provisional Patent Application, 62/595,344, filed Dec. 6,2017, both of which are incorporated by reference herein in theirentireties.

BACKGROUND

External fixation systems are used to build frames that hold bonefixation elements, such as pins, bars, or rods, rigidly. The variabilityof the different conditions treated, such as bone fractures, requiresversatility of alignment and sizing of the fixator frame. A very commonstyle of external fixation system uses fixation elements, i.e. bars andbone pins, and clamps that hold the fixation elements together.Commonly, both pins and bars have circular cross sections, buttypically, the bars are a larger diameter than the pins. For largeframes for the leg and arm, the most common size bar is 11 mm, but theymay vary between 8 and 13 mm, and the most common size pin is 5 mm, butthey may vary between 3 and 6 mm. Clamps are used to join pins to barsand bars to other bars. The most common type of clamp has a threadedshaft that can squeeze together two jaw sets, clamping them together andclamping an element in each jaw set. Although a jaw set can beconfigured to grab a range of sizes of elements, fitting elements thathave an over two times difference in diameter in a jaw set that is bothcompact in size and effective in locking strength has been a challenge.For this reason, most clamp systems have jaws configured to either graba bar or a pin, and therefore have a clamp that is configured to grab abar in one jaw set and a pin in another jaw set and another separateclamp assembly that is configured to grab a bar in each jaw set.

Having separate clamps for joining two bars versus joining a bar to apin can lead to problems. The user can accidentally get handed the wrongone during a medical procedure, leading to wasted time. The shafttightening element can be in an inconvenient location for the desiredframe geometry. Also, the number of clamps needing to be sterilized andmade available for each case is increased. To overcome some of theseshortcomings, clamps that can accept bars and pins in each jaw set havebeen developed. One of the earliest is the Synthes combination clampthat has two grooves on each jaw in the jaw set, one groove sized forbars and one sized for pins. These jaws accept the bar or pin element byspreading apart to allow the element into the groove, and they grip theelement by being squeezed together via the shaft onto the element.

FIGS. 1a and 1b show such a conventional clamp 10. This clamp has afirst jaw set 11 and a second similar jaw set 11 a. The two jaw sets aresimilar, so the similar items in the second jaw set are numbered thesame as the first jaw set but have an “a” appended. Each jaw set isconfigured to hold either of a first fixation element 12 or a secondfixation element 13. In some examples, the first jaw set includes anouter jaw 15 and an inner jaw 16. The outer jaw 15 has a first groove 17and a second groove 18. The inner jaw 16 has a first groove 19 and asecond groove 20. The first grooves 17 and 19 form a first passage 21,and the second grooves 18 and 20 form a second passage 22. The firstelement 12 can be placed in the first passage 21 and the inner jaw 16and outer jaw 15 open slightly, contacting near the second passage 22 atan edge 23. As shown in FIG. 1a , in the second jaw set 11 a, a secondelement 13 may be placed in the second passage 22 a. The inner jaw 16 aand outer jaw 15 a open slightly, contacting near the first passage 21 aat edge 24. As shown in FIG. 1b , when a third element 14 of a similarsize to the first element 12 is placed in the first passage 21 a, thesecond jaw set 11 a may contact on the edge 23 a. In variousembodiments, to clamp the elements into the jaw sets, a threaded shaft25 and nut 26 may be tightened compressing both jaw sets and theelements. Because the edges in contact 23 and 24 are closer to the forceof clamping than the elements 12, 13, or 14, the edges may carry agreater share of the clamping load. Also, because both the first passage21 and second passage 22 are accessible to the user, an element mightmistakenly be introduced into a jaw set when another element is alreadyin place, forcing the two elements to be parallel. Although there may bean instance where this is desired, most often the goal is to get theelements clamped together in a non-parallel orientation.

Another concept by Chreene and Austin (U.S. Pat. No. 8,821,491) issimilar, but the jaws in each set slide laterally relative to each otherto allow the bar or pin element to enter the jaw. The Chreene clampgrips the element by being squeezed onto the element as well.

Both the Synthes combination clamp and the Chreene design havedrawbacks. One example drawback is that the amount of force transferredto the element by the jaw geometry is reduced relative to a standard onesided clamp. In these two-jaw style clamp designs, the locking forcegenerated by the shaft is split between the clamping of the element andthe reaction force between the two jaws where they pivot. Because thelocation of contact between the two jaws is moved closer to the line ofaction of the clamping force, the relative reaction force at thislocation goes up, and the reaction force acting between the jaw and theelement goes down.

Another jaw set that can hold more than one size of element is shown inCremer et al (U.S. Pat. No. 8,827,997). The jaw set used to clamp theelement has three, and only three, sets of passages. Each set ofpassages is designed to hold an element of a particular size. It hassimilar drawbacks to the two-sided designs discussed above.

Another method used to clamp elements of vastly different sizes is shownby Brown and Denlinger (US Patent Publication 2009/0036891). The jaw sethas two passages located on one side of the clamping fastener, a smallerpassage close to the fastener and a larger passage further from thefastener.

Another method to clamp elements of varying sizes is shown by Miller andMullaney (U.S. Pat. No. 9,138,260), where the jaw set has a passage orother clamping means on one side of the fastener. On the other side ofthe fastener, a spacer that has steps or catches is interposed betweenthe jaws. Depending upon where the spacer is positioned, the jaw isarranged to hold an element of a specific size by allowing the jaws tomove to a position where the passage is allowed to open to a particularsize. The primary purpose of the spacer in this design is to configurethe clamp to provisionally lock the element when the spacer is in thecorrect position. One drawback of this design is the spacer can move tothe wrong position such that the jaw set is configured for a differentelement size than intended. Another drawback is that it is difficult toconfigure the jaw passage and the steps such that elements of as much astwo times difference in size can be effectively gripped.

Accordingly, there is a need for additional external fixation clampsthat may address at least one of the deficiencies in the state of theart, whether stated above or unstated.

BRIEF SUMMARY OF THE INVENTION

Consistent with some embodiments, the basic design of an externalfixation system clamp incorporates a jaw set that grips the fixationelement and a fastener that squeezes the jaw set together. Most clampshave two jaw sets so that two fixation elements can be clamped together,but a single jaw set may be attached to another device to clamp afixation element to that other device. Each jaw set is made up of twojaw halves. Usually, the jaw halves are separate components that restagainst each other, with a first end of each component forming a passagefor accepting the fixation element and a second end of the componentbalancing the clamping load. The fastener that applies the clamping loadmay be interposed between the passage and the back end of the jawcomponent.

A first benefit of the systems described herein is the ability to clampdifferently sized or shaped elements in a single jaw set. Most externalfixation systems have a variety of differently sized elements. The mostcommon pattern is a larger bar for spanning across the defect and asmaller pin for fixing into the bone. By having a jaw set that can grabeither the bar or the pin, or any of two fixation elements, the jaw setcan be used in a variety of situations. This reduces the need for anumber of different clamps with different jaw sets specific to eachfixation element.

A second benefit of systems described herein is that they may provide ahigher clamping load onto the fixation element for the same fastenerload. Other devices which allow for a jaw set to grip more than one sizefastener have a compromise in their geometry that reduces the amount offastener load transferred through the fixation element due to thebalance of forces on the jaws. By utilizing the slider to position thereaction force further from the fastener load, the grip force utilizes ahigher amount of the fastener load. This benefits the user because theycan get better stability when pre-tightening the clamp using just fingerforce. Finger force may be sufficient to keep the clamp from slipping onthem prior to final tightening. Further, final tightening will be morestable for the same amount of load applied to the fastener.

An example embodiment described herein comprises jaw components, eachwith a groove on a first end together forming a passage for a largerfixation element and grooves on the opposite second end together forminga passage for a smaller fixation element. Positioned between these twojaw components is a slider. When a fixation element is introduced intothe desired passage, the slider is moved towards the unused passage. Theslider is positioned so the clamping force is transmitted from one jawcomponent to the other through the fixation element and the slider. Theslider is configured so that the contact point between the outer jaw andslider and between the slider and inner jaw is located in a positionaway from the fastener opposite the fixation element.

The fastener applies load to the outer jaw, which shares this loadbetween the element and the slider. The further the contact point withthe slider is moved away from the fastener, the higher the amount ofload sharing that is sent through the element. Conventional combinationclamps which do not have a slider have a contact point that is veryclose to the fastener, which means that a high share of the load goesthrough the contact point and a low share goes through the element.

An example embodiment comprises a slider interposed between two jawsthat tip up and down relative to each other to allow the fixationelement into the passage. Another configuration positions a sliderbetween an inner jaw and an outer jaw, where the outer jaw slidesrelative to the inner jaw to allow the fixation element into thepassage. To apply load to the fastener in either passage, the fastenermust be slightly larger than the passage. For the conventional slidinghead clamp, the outer jaw must tip relative to the inner jaw to allowthe outer jaw to slide back in place. Although this tipping will besmall, in practice, the fastener loads the outer jaw unevenly. In oneembodiment of the invention, the outer jaw and slider are configured tocontact only at the point furthest from the retained fastener. The outerjaw has a relief in the track where it contacts the slider. When thefixation element is in place, the slider is moved to a point where thenear side is located adjacent to the relief and the far side is incontact with the outer jaw.

The jaw set can be connected to a matching jaw set. The exampleembodiment shows radial serrations on the inside of the inner jaw thatcan interface with matching serrations on a matching inner jaw of thematching jaw set. These same serrations can mate with matchingserrations on other devices as well. When the fastener is tightened, theserrations lock together while the fixation element is clamped.

The jaw set can be mated to other jaw sets or other devices throughother means. One embodiment attaches the jaw set to a ball joint, so thejaw set can swivel relative to the other device. Another embodiment hasthe inner jaw mated to a saddle so the jaw set can roll relative to theother device.

In yet another exemplary aspect, the device may be an external fixationframe that includes a clamp with a jaw set where one side is configuredto hold a first element and the other side of the jaw set is configuredto hold a second, differently shaped or sized element, where a slider isinterposed between the first jaw of the jaw set and the second jaw ofthe jaw set, and where the slider slides between a first position and asecond position where the first position aids in holding the firstelement and the second position aids in holding the second element.

In an exemplary aspect, the present disclosure is directed to anexternal fixation clamp configured to hold a fixation element. Theexternal fixation clamp may include an inner jaw with a first end shapedto engage a first size fixation element and a second end shaped toengage a second size fixation element. An outer jaw may include a firstend shaped to engage the first size fixation element and a second endshaped to engage the second size fixation element. A fastener may beconfigured to clamp the inner jaw and the outer jaw to at least one ofthe first and the second fixation elements, and the fastener may have anaxis. A sliding spacer may be interposed between the inner jaw and theouter jaw and may be arranged to slide in a direction transverse to theaxis of the fastener. The sliding spacer may be structurally associatedwith the inner jaw and the outer jaw so that when the first sizefixation element is introduced between the inner jaw and the outer jaw,the sliding spacer moves to a first position where the sliding spacerand at least one of the inner jaw and the outer jaw are in contact at afirst point away from the fastener. When the second size fixationelement is introduced between the inner jaw and the outer jaw, thesliding spacer may move to a second position where the sliding spacerand at least one of the inner jaw and the outer jaw are in contact at asecond point away from the fastener.

In some aspects, the outer jaw is configured to tilt relative to theinner jaw to allow the fixation element to enter between the inner jawand the outer jaw. In some aspects, the outer jaw slides relative to theinner jaw to allow the fixation element to enter between the inner jawand the outer jaw. In some aspects, the first ends of the inner jaw andthe outer jaw are configured to hold a fixation element of a diameterbetween 10 and 13 mm, and the second ends of the inner jaw and the outerjaw are configured to hold a fixation element of a diameter between 3and 6.5 mm. In some aspects, the first ends of the inner jaw and theouter jaw are configured to hold a fixation element of a diameterbetween 6 and 9 mm, and the second ends of the inner jaw and the outerjaw are configured to hold a fixation element of a diameter between 3and 5 mm. In some aspects, the first ends of the inner jaw and the outerjaw are configured to hold a fixation element of a diameter between 4and 6 mm, and the second ends of the inner jaw and the outer jaw areconfigured to hold a fixation element of a diameter between 2 and 4 mm.In some aspects, the first ends of the inner jaw and the outer jaw areconfigured to hold a fixation element of a diameter of 11 mm, and thesecond ends of the inner jaw and the outer jaw are configured to hold afixation element of a diameter of 5 mm. In some aspects, the clampfurther includes a second inner jaw disposed along the axis relative tothe first inner jaw; and a second outer jaw, wherein the second innerand second outer jaws are disposed to cooperatively grip a secondfixation element. In some aspects, the clamp may include a saddlecomponent, and the inner jaw may be configured to mate with the saddlecomponent in a manner that allows the inner jaw, the outer jaw, and thesliding spacer to roll about an angle transverse to an axis of one ofthe first size fixation element and the second size fixation element andalso transverse to the axis of the fastener. In some aspects, the innerjaw is configured to mate with a ball such that the inner jaw and theouter jaw is configured to pitch, roll, and yaw relative to a devicecomprising the ball.

In another exemplary aspect, the present disclosure is directed to a jawset of an external fixation clamp. The jaw set may include an inner jawwith a first end configured to engage a first fixation element and asecond end configured to engage a second fixation element, an outer jawwith a first end configured to engage the first fixation element and asecond end configured to engage the second fixation element, and afastener configured to clamp the inner jaw and the outer jaw to one ofthe first fixation element and the second fixation element. The fastenermay have an axis. A sliding spacer may cooperatively engage the innerjaw and the outer jaw and may slide in a direction transverse to theaxis of the fastener and transverse to an axis of said one of the firstfixation element and the second fixation element when said one of thefirst fixation element and the second fixation element is disposedbetween the inner jaw and the outer jaw. When said one of the firstfixation element and the second fixation element is introduced betweenthe first end of the inner jaw and the first end of the outer jaw, thesliding spacer may move to a first position where the sliding spacer andat least one of the inner jaw and the outer jaw are in contact at afirst location near the second end of the inner jaw or the outer jaw.Alternatively, when said one of the first fixation element and thesecond fixation element is introduced between the second end of theinner jaw and the outer jaw, the sliding spacer may move to a secondposition such that the sliding spacer and at least one of the inner jawand the outer jaw are in contact at a second location near the first endof the inner jaw or the outer jaw.

In an aspect, the first end of the inner jaw and the first end of theouter jaw form a first passage configured to hold the first fixationelement of a first size and the second end of the inner jaw and thesecond end of the outer jaw form a second passage configured to hold thesecond fixation element of a second size different than the first size.In an aspect, the first end of the inner jaw and the first end of theouter jaw form a first passage configured to hold the first fixationelement when the first fixation element is a non-cylindrical element andthe second end of the inner jaw and the second end of the outer jaw forma second passage configured to hold the second fixation element when thesecond fixation element is a different shape than the non-cylindricalelement. In an aspect, the second end of the inner jaw and the secondend of the outer jaw form are configured to hold the second fixationelement when the second fixation element is a cylindrical element. In anaspect, the second end of the inner jaw and the second end of the outerjaw form are configured to hold the second fixation element when thesecond fixation element is proportionally the same shape as the firstfixation element but a different size from the first fixation element.

In another exemplary aspect, the present disclosure is directed to anexternal fixation clamp configured to grip a size-range of fixationelements. The clamp may include an inner jaw with a first end and asecond end, and may also include an outer jaw with a first end and asecond end. The first end of the inner jaw and the first end of theouter jaw may be disposed to cooperatively form a first passage sized togrip a first fixation element having a first size. The second end of theinner jaw and the second end of the outer jaw may be disposed tocooperatively form a second passage sized to grip a second fixationelement having a second size. A fastener may be configured to clamp theinner jaw and the outer jaw to at least one of the first and the secondfixation elements. The fastener may have a fastener axis. A spacer maybe slidingly moveable relative to the inner jaw and the outer jaw. Thespacer may be arranged to slide and intersect the second passage whenthe first fixation element having a first size is introduced to thefirst passage. The spacer may be arranged to slide and intersect thefirst passage when the second fixation element having a second size isintroduced to the second passage.

In another exemplary aspect, the present disclosure is directed to anexternal fixation clamp configured to grip a size-range of fixationelements. The clamp may include the inner jaw, the outer jaw, thefastener, and the spacer. The spacer may be slidingly moveable relativeto the inner jaw and the outer jaw and slidable between the first andthe second passages. The spacer may engage one of the inner jaw and theouter jaw at a first fulcrum point when the first fixation elementhaving a first size is introduced to the first passage. The spacer mayengage one of the inner jaw and the outer jaw at a second fulcrum pointwhen the second fixation element having a second size is introduced tothe second passage. The first fulcrum point may be disposed on a firstlateral side of the fastener axis and the second fulcrum point may bedisposed on a second different lateral side of the fastener axis.

In another exemplary aspect, the present disclosure is directed to anexternal fixation clamp jaw set having an outer jaw, an inner jaw, and afastener. The claim may also have a swivel component with a convexsurface shaped to mate to the concave surface of the inner jaw. Theinner jaw may be configured to mate with the swivel component and allowthe inner jaw and the outer jaw to roll about an axis transverse to boththe axis of the fixation element and the axis of the fastener.

In an aspect, the second end of the inner jaw and the second end of theouter jaw are disposed to cooperatively form a second passage sized togrip a second fixation element having a second size. The clamp jaw setmay further include a sliding spacer slidably associated with the innerjaw and the outer jaw to slide in a direction transverse to the axis ofthe fastener. The spacer may be structurally associated with the innerjaw and the outer jaw so that when the first size fixation element isintroduced into the first passage, the sliding spacer moves to a firstposition where the sliding spacer and at least one of the inner and theouter jaws are in contact at a first location away from the fastener.Alternately, when the second size fixation element is introduced intothe second passage, the sliding spacer may move to a second positionwhere the sliding spacer and at least one of the inner and the outerjaws are in contact at a second location away from the fastener.

In an aspect, the swivel component is configured to lock the first andthe second jaws at a tilt relative to the fastener at the same time thefastener clamps the inner jaw and the outer jaw to at least one fixationelement. In an aspect, the convex surface of the swivel component is atoroidal shape. In an aspect, the convex surface of the swivel componentis a cylindrical shape. In an aspect, the convex surface of the swivelcomponent is a shape consisting of two cones. In an aspect, the convexsurface of the swivel component is a partial sphere. In an aspect, theswivel component has a serrated surface opposite the convex surface. Inan aspect, the outer jaw has a convex surface. In an aspect, the convexsurface of the outer jaw mates with a flat surface of the fastener. Inan aspect, the convex surface of the outer jaw mates with a washerinterposed between the outer jaw and the fastener. In an aspect, thewasher incorporates a convex surface to contact the outer jaw.

In an aspect, the present disclosure is directed to an external fixationclamp that includes a jaw set including an outer jaw and an inner jawforming a passage therebetween. The jaw set may be configured to capturea rigid fixation element within the passage. The inner jaw may have aconcave cavity on the surface facing away from the outer jaw. A clampingmechanism may be arranged to maintain an axial alignment of the outerjaw and the inner jaw. A reference component may be offset along thelongitudinal axis from the jaw pair. A coupling mechanism may bearranged between the jaw set and the reference component. The couplingmechanism may allow the jaw set to rotate relative to the referencecomponent about the longitudinal axis. The coupling mechanism mayinclude a convex surface interfacing with the concave cavity on thesurface of the inner jaw facing away from the outer jaw, and the jaw setmay be pivotable on the coupling mechanism about a transverse axis thatis perpendicular to the longitudinal axis.

In an aspect, the clamping mechanism is a nut combined with a threadedstud. In an aspect, the nut comprises a flat surface that articulatesagainst a curved outer surface of the outer jaw, and the nut may berotatable to lock articulation of the jaw set when tightened on thestud. In an aspect, the clamp may include a washer between the nut andthe curved outer surface of the outer jaw. In an aspect, the washercomprises a curved surface that fits against the curved outer surface ofthe outer jaw. In an aspect, the jaw set is configured to capture arigid element of a second size.

In an aspect, reference component consists of an external fixation clampconfigured to hold a fixation element. The reference component mayinclude an inner jaw with a first end shaped to engage a first sizefixation element and a second end shaped to engage a second sizefixation element. An outer jaw with a first end may be shaped to engagethe first size fixation element and a second end shaped to engage thesecond size fixation element. A fastener may be configured to clamp thejaws to at least one of the first and the second fixation elements, thefastener having an axis. A sliding spacer may be interposed between thejaws arranged to slide in a direction transverse to the axis of thefastener. In an aspect, the clamping mechanism locks both fixationelements and the articulation device when applying clamping force.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate embodiments of the devices andmethods disclosed herein and together with the description, serve toexplain the principles of the present disclosure.

FIG. 1a shows a conventional device with jaw sets that have two passageswhere the first passage is configured to hold an element of a first sizeand the second passage is configured to hold an element of a differentsize.

FIG. 1b shows a conventional device with jaw sets that have two passageswhere the first passage of both jaw sets is configured to hold anelement of the first size.

FIG. 2 shows one type of simple external fixation frame that uses clampswhich incorporate the jaw sets of the present invention according to oneor more aspects of the present disclosure.

FIG. 3 is a perspective view of a clamp according to one or more aspectsof the present disclosure.

FIG. 4 is a perspective view of a jaw set of FIG. 3 according to one ormore aspects of the present disclosure.

FIG. 5 shows a plan view of the clamp of FIG. 3 according to one or moreaspects of the present disclosure.

FIG. 6 shows a partial section view of the clamp taken through line112-112 in FIG. 5 according to one or more aspects of the presentdisclosure.

FIG. 7a shows an exploded view of the jaw set according to one or moreaspects of the present disclosure.

FIG. 7b shows another exploded view of the jaw set according to one ormore aspects of the present disclosure.

FIG. 8 shows the jaw set holding an element of a first size in the firstpassage according to one or more aspects of the present disclosure.

FIG. 9 shows the jaw set holding an element of a second size in thesecond passage according to one or more aspects of the presentdisclosure.

FIG. 10 shows a perspective view of a clamp made with a secondembodiment jaw set where the jaws slide relative to each other accordingto one or more aspects of the present disclosure.

FIG. 11 shows a section view of the second embodiment jaw set accordingto one or more aspects of the present disclosure.

FIG. 12 shows the second embodiment jaw set gripping a first element inthe first passage according to one or more aspects of the presentdisclosure.

FIG. 13 shows the second embodiment jaw set gripping a second element ofa different size than the first element in the second passage accordingto one or more aspects of the present disclosure.

FIG. 14 shows a clamp made from a third embodiment jaw set where the jawset is configured to tilt relative to the shaft according to one or moreaspects of the present disclosure.

FIG. 15 shows the clamp with the third embodiment jaw set as seen fromthe side according to one or more aspects of the present disclosure.

FIG. 16 shows a section view taken through line 312-312 in FIG. 15showing the interface between the inner jaw and the saddle according toone or more aspects of the present disclosure.

FIG. 17 shows a section view perpendicular to the view shown in FIG. 16according to one or more aspects of the present disclosure.

FIG. 18 shows a fourth embodiment of the invention where the inner jawmates with another device via a ball joint according to one or moreaspects of the present disclosure.

FIG. 19 shows the section view of the fourth embodiment, showing theinner jaw ball and inner jaw socket configuration according to one ormore aspects of the present disclosure.

FIG. 20 shows a fifth embodiment of a clamp that incorporates a swivelelement that allows the jaw set to tilt relative to the shaft accordingto one or more aspects of the current disclosure.

FIG. 21 shows the fifth embodiment clamp from a second perspectiveaccording to one or more aspects of the present disclosure.

FIG. 22 shows the fifth embodiment clamp where the jaw set is tiltedrelative to the shaft according to one or more aspects of the presentdisclosure.

FIG. 23 shows a section view of the fifth embodiment clamp according toone or more aspects of the present disclosure.

FIG. 24 shows a second section view of the fifth embodiment clampaccording to one or more aspects of the present disclosure.

FIG. 25 shows a third section view of the fifth embodiment clamp wherethe jaw set is tilted relative to the shaft according to one or moreaspects of the present disclosure.

FIGS. 26a, 26b, 26c, and 26d are graphs showing grip forces of clampsaccording to the present disclosure compared to conventional clamps inFIGS. 1a and 1 b.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of thepresent disclosure, reference will now be made to the embodimentsillustrated in the drawings, and specific language will be used todescribe the same. It will nevertheless be understood that no limitationof the scope of the disclosure is intended. Any alterations and furthermodifications to the described devices, instruments, methods, and anyfurther application of the principles of the present disclosure arefully contemplated as would normally occur to one skilled in the art towhich the disclosure relates. In particular, it is fully contemplatedthat the features, components, and/or steps described with respect toone embodiment may be combined with the features, components, and/orsteps described with respect to other embodiments of the presentdisclosure.

FIG. 2 shows one type of external fixation frame 1. The frame may beheld together with a number of clamps 2, 2 a, 2 b, 2 c, 2 d, 2 e. Eachclamp may hold two fixation elements together. In an exemplaryembodiment, they hold bars 3, 3 a, 3 b and bone pins 4, 4 a, 4 b, 4 c.The bone pins are fixed into the bone 5. The rods and bone pins aresignificantly different sizes. Here, the different sizes are representedby cross-section widths, which may be diameters. The sizes may vary andin some implementations, the sizes of the bars may be double or morethan double the sizes of the pins. In some implementations however, thesizes of the bars may be less than double the size of the pins. Theclamps, in this depiction, are all the same style and design. The clampsincorporate jaw sets of the present invention such that the clamps caneffectively clamp a bar to another bar or can clamp a bar to a pin.Different configurations of clamp 2 are discussed below, and other typesof clamps are contemplated.

FIG. 3 is a perspective view of an external fixation clamp assembly 100made with the example embodiment jaw set 101 according to one or moreaspects of the present disclosure. The jaw set 101 includes an outer jaw106, a spacer 107, and an inner jaw 108. Here, this clamp assembly 100may incorporate a second similar jaw set 102, but depending on theimplementation and the embodiment, other jaw sets or other externalfixation devices could be mated to the first jaw set in place of or inaddition to the jaw set 102. To apply clamping force to the jaw set 101,a threaded shaft 103 (also referred to herein as a fastener) and nut 104act on the other jaw set 102 and a washer 105. The washer 105 may beseated on the outside of the outer jaw 106 of the jaw set 101. In someexamples, the outer jaw 106 may rest against the spacer 107 which mayrest against the inner jaw 108. In this example implementation, thesecond jaw set 102 in FIG. 3 includes a similar washer 105 a, outer jaw106 a, spacer 107 a, and inner jaw 108 a. In some embodiments and asshown in FIG. 3, the inner jaw 108, 108 a may have rotation resistingserrations 109 which seat into similar serrations 109 a on the opposingcomponent, which in this example is the inner jaw 108 a of the jaw set102. Other rotation resisting features are contemplated, which mayinclude relying solely on the force of friction. The threaded shaft orfastener may define an axis that is coaxial with the threaded shaft,which may also define an axis of the fixation clamp assembly 100.

In some implementations described in FIG. 3 and in other embodimentsthroughout this disclosure, the threaded shaft 103 (or fastener) and thenut 104 may form a clamping mechanism arranged to maintain an axialalignment of the outer jaw and the inner jaw.

Furthermore, although FIG. 3 shows the first jaw set 101 and the secondjaw set 102, the second jaw set 102 may also be referred to as areference component. Although shown as a jaw set, the referencecomponent may be a different component, such as a stabilizer, amulti-pin clamp, or other component that may be used as a reference whenthe first jaw set 101 is rotated, pivoted, or otherwise displaced tomanipulate a fixation element.

FIG. 4 shows the jaw set 101 in a perspective view according to one ormore aspects of the present disclosure. The outer jaw 106 of the jaw set101 may incorporate a seat 114 for the washer and a bore 115 throughwhich the shaft 103 may pass through. Depending on the embodiment, theseat may be a tapered at an angle, may be bowl-shaped, or may have someother shape.

FIG. 5 shows the clamp from FIG. 3 from a side view according to one ormore aspects of the present disclosure. Visible in this view is a spring111, which in some embodiments may bias and selectively hold the jawsets apart. The spring is a biasing feature that may make the clampeasier to snap onto the fixation element and remain in place prior totightening, but the spring may not be required for the device tofunction. Tightening the nut 104 compresses the jaw sets 101, 102against the head of the shaft 103. A line 112-112 is drawn to showsubstantially the center of the shaft.

FIG. 6 is a section view taken through FIG. 5 along line 112-112according to one or more aspects of the present disclosure. In someembodiments, the section view shows that the outer jaw 106 may have afirst groove 121 and a second groove 122. The first and second grooves121, 122 are the same size in FIG. 6, but they may have different sizes,including having a groove on only one of the jaws. They are shown asexactly opposing each other in this implementation, but may be partiallyoffset in other implementations. Similarly, the inner jaw 108 may have athird groove 123 and a fourth groove 124. When the jaw set 101 isassembled, the first and third groove 121, 123 may combine to form afirst passage 125 to grip a fixation element, and the second and fourthgroove 122, 124 may combine to form a second passage 126 to grip adifferently sized fixation element.

FIGS. 7a and 7b show an exploded view of the jaw set 101 from twodifferent perspectives according to one or more aspects of the presentdisclosure. In some embodiments, the inner jaw 108 shows a track 133with a bearing surface 134. The spacer 107 may have a bearing surface132 that contacts the inner jaw 106 on the mating bearing surface 134.The spacer may also have bearing surfaces 137 and 138 on its oppositeside. In some embodiments, the outer jaw 106 shows a track 135 with abearing surface 136. The outer jaw bearing surface 136 may contact thespacer bearing surface 137 and 138. In an exemplary embodiment, sinceeach of the outer jaw 106, the spacer 107, and the inner jaw 108 issymmetrical, each has additional symmetrically matching bearing surfaces132 a, 137 a, 138 a, and not shown, 134 a, 136 a. In variousembodiments, on the spacer 107, between bearing surfaces 137 and 138,there is a relief 139 shown in FIG. 7a . In an exemplary embodiment,bearing surfaces 137 and 138 are coplanar surfaces, but otherarrangements are contemplated. Edge 131 is shown at the outer edge ofbearing surface 137. Edge 141 may be located on the other side of thespacer 107 at the outer edge of bearing surface 138. Similar edges 131 aand 141 a may be located at the outer edges of surfaces 137 a and 138 a.

The outer jaw 106 and the inner jaw 108 each include twoelement-receiving ends, that in this implementation are opposed to eachother. Here, the outer jaw 106 includes a first element-receiving end150 and a second element-receiving end 151. The inner jaw 108 alsoincludes a first element-receiving end 152 and a secondelement-receiving end 153. Each of the element-receiving ends 150, 151,152, 153 are shaped to engage a fixation element, such as a bar or a pinintroduced into the jaw set formed by the outer jaw and the inner jaw.In the embodiment shown, first element-receiving ends 150, 152 of theouter and inner jaws 106, 108 are shaped to engage a first size fixationelement and the second element-receiving ends 150, 152 of the outer andinner jaws 106, 108 are shaped to engage a second size fixation element.In the implementation shown, the first element receiving end 150 of theouter jaw 106 and the first element receiving end 152 of the inner jaw108 cooperate to define the passage 125. Likewise, the second elementreceiving end 151 of the outer jaw 106 and the second element receivingend 154 of the inner jaw 108 cooperate to define the passage 126.

FIG. 8 shows the jaw set 101 in a first position where the slidingspacer 107 and at least one of the inner and outer jaws 108, 106 are incontact at a first point away from the fixation element and away fromthe fastener or threaded shaft 103. Here, a fixation element 130 may belocated in the first passage 125 of the jaw set 101. In this embodiment,the element 130 may be a fixation bar, having a size or diameter greaterthan a size or diameter of a fixation pin. In an exemplary embodiment,the spacer 107 is moved away from the first passage 125, and the outerjaw 106 is in contact with the spacer 107 at contact points thatcorrespond to the reference number 131 in FIG. 8 on the outer edges 131,131 a of the spacer 107 furthest from the element. The contact pointthat corresponds to the reference numbers 131 in FIG. 8 may act as afulcrum for the outer jaw to pivot or rotate to increase or decrease thewidth of the passage 125. Although shown as a contact point with theouter jaw 106, other embodiments utilize a contact point or contactfulcrum with the inner jaw, while yet other embodiments utilize contactpoints or contact fulcrums on both the inner and outer jaws 108, 106 atthe same time. Because the spacer may be displaced away from the element130, the edges in contact may be located away from the shaft 103. In theconfiguration shown in FIG. 8, the spacer 107 is also preventingintroduction of an element into the second passage 126. It may do thisbecause the sliding spacer 107 intersects with the first passage 126 andmechanically interferes or blocks introduction of an element into thesecond passage. It is worth noting that some implementations of thespacer 107 includes a depression or recess portion that may engage orabut against the outer surface shape of the fixation element 130.

FIG. 9 shows the jaw set 101 in a second position where the slidingspacer 107 and at least one of the inner and outer jaws 108, 106 are incontact at a second point away from the fixation element and away fromthe fastener or threaded shaft 103. Here, a fixation element 140 may belocated in the second passage 126 of the jaw set 101. In thisembodiment, the element 140 may be a fixation pin, having a size ordiameter less than a size or diameter of a fixation bar. In an exemplaryembodiment, the spacer 107 is moved to the other end of the jaw set, andthe outer jaw 106 is in contact with the spacer 107 at contact pointsthat correspond to the reference numbers 141 in FIG. 9 on the otherouter edges 141, 141 a of the spacer, furthest from the second element140. The contact point that corresponds to the reference numbers 141 inFIG. 9 may act as a fulcrum for the outer jaw to pivot or rotate toincrease or decrease the width of the passage 126. Although shown as acontact point with the outer jaw 106, other embodiments utilize acontact point or contact fulcrum with the inner jaw, while yet otherembodiments utilize contact points or contact fulcrums on both the innerand outer jaws 108, 106 at the same time. Also, in the configurationshown in FIG. 9, the spacer 107 is located so no element can beintroduced into the first passage 125. It may do this because thesliding spacer 107 intersects with the first passage 125 andmechanically interferes or blocks introduction of an element into thefirst passage 125.

The spacer 107 in FIG. 9 operates differently than known latches likethat described in U.S. Pat. No. 9,138,260. The known latch is providedto provisionally lock the outer and inner jaw to resist them fromopening and allowing the fixation element to be removed. The known latchslides into alternative positions depending upon the size of thefixation element being gripped, but the fixation element is alwaysgripped by the first end of the jaw set, and the latch always contactsthe second end of the jaw set. In contrast, the sliding spacer 107described herein is configured to contact the second end of the jaw setwhen the first end holds a fixation element, and to contact the firstend when the second end holds a fixation element. As can be seen inFIGS. 8 and 9, the outer jaw 106 is configured to tilt relative to theinner jaw 108 to allow the fixation elements 130, 140 to enter betweenthe outer and inner jaws 106, 108.

FIG. 10 is a perspective view of an external fixation clamp assembly 200made with an alternative embodiment jaw set 201 according to one or moreaspects of the present disclosure. Some features are similar to or thesame as described with reference to the other embodiments, and will notbe re-described here. This clamp may incorporate a second similar jawset 202, but other jaw sets or other external fixation devices could bemated to the first jaw set as described above with reference to theclamp assembly 100. To apply clamping force to the jaw set, a threadedshaft 203 and nut 204 act on the other jaw set 202 or an alternativefixation device in place of the jaw set 202. In some embodiments, theouter jaw 206 rests against the spacer 207 which rests against the innerjaw 208. The second device in FIG. 10 is also an alternative embodimentjaw set, so there is a similar outer jaw 206 a, spacer 207 a, and innerjaw 208 a. The inner jaw may have rotation resisting serrations 209which seat into similar serrations 209 a on the other device 202,although other rotation resisting features are contemplated, includingrelying solely on the force of friction.

FIG. 11 is a section view of the device through the axis of the shaftand perpendicular to the axis of any fixation element according to oneor more aspects of the present disclosure. Visible in this view is abiasing member shown as a spring 211 which may bias or selectively holdthe jaw sets apart. The spring is a biasing feature that makes the clampeasier to snap onto the fixation element and remain in place prior totightening, but the spring may not be required for the device tofunction. Other biasing elements are contemplated to be added to thisdevice, including biasing elements that return the spacer 207 or theouter jaw 206 to the middle position relative to the inner jaw 208. FIG.11 shows how tightening the nut 204 can compress the jaw sets 201, 202against the head of the shaft 203. FIG. 11 shows that, in someembodiments, the outer jaw 206 may have a first groove 221 and a secondgroove 222. Similarly, the inner jaw 208 may have a third groove 223 anda fourth groove 224. When the jaw set 201 is assembled, the first andthird groove 221, 223 may combine to form a first passage 225 to grip afixation element, and the second and fourth groove 222, 224 may combineto form a second passage 226 to grip a differently sized fixationelement.

FIG. 12 shows a fixation element 230 located in the first passage 225 ofthe jaw set according to one or more aspects of the present disclosure.In an exemplary embodiment, to insert the fixation element 230 into thepassage 225, the outer jaw 206 and spacer 207 are moved transverselyrelative to the inner jaw 208 and shaft 203. In a further exemplaryembodiment, to hold the fixation element 230 in the passage 225, theouter jaw 206 is moved back in the position to form the passage 225. Itis contemplated that in various embodiments a biasing element can beused to return the outer jaw 206 into position, but the embodiment asshown in FIG. 12 (which is a non-limiting embodiment) is configured tohave that step performed by the user. In an exemplary embodiment, thespacer 207 remains in a position away from the first passage, and theouter jaw 206 is in contact with the spacer 207 on the outer edge 231 ofthe spacer 207 furthest from the element 230. Because the spacer isdisplaced away from the element, the edge in contact is located awayfrom the shaft 203. In the configuration shown in FIG. 12, the spacer isalso preventing introduction of an element into the second passage.

FIG. 13 shows a second fixation element 240 located in the secondpassage 226 of the jaw set 201 according to one or more aspects of thepresent disclosure. In an exemplary embodiment, to introduce the element240 into the passage 226, the outer jaw 206 and spacer 207 are movedtransversely relative to the inner jaw 208 and shaft 203. In a furtherexemplary embodiment, to hold the fixation element 240 in the passage226, the outer jaw 206 is moved back in the position to form the passage226. The spacer 207 remains in a position away from the second passage.In some embodiments, the outer jaw 206 is in contact with the spacer 207on the other outer edge 241 of the spacer 207, furthest from the secondelement. Also, in the configuration shown in FIG. 13, the spacer 207 islocated so no element can be introduced into the first passage.

FIG. 14 shows an alternative embodiment according to one or more aspectsof the present disclosure. Some features are similar to or the same asdescribed with reference to the other embodiments, and will not bere-described here. In some embodiments, a clamp 300 may be made from ajaw set 301 and a jaw set 302. Jaw set 301 may include an outer jaw 306,a spacer 307, and an inner jaw 308 and may be configured similar to theexample embodiments discussed above, including the jaw set 101. Thealternative embodiment jaw set 302, may be made from a similar outer jaw306 a and spacer 307 a, but the inner jaw 341, is, in some embodiments,configured to mate with a saddle 342. The saddle 342 may incorporateserrations 343 that mate with the serrations 309 on the inner jaw 308.To clamp the two jaw sets 301, 302 together, there is a threaded shaft303 and a nut 304. Optional washers 305, 305 a are shown in thisembodiment. In some implementations, the saddle may be referred to as acoupling mechanism arranged to couple the two jaw sets 301, 302together.

In FIG. 15, a side view of the clamp is shown according to one or moreaspects of the present disclosure. A line 312-312 is shown substantiallydown the center of the clamp. Visible in this view is a biasing elementshown as a spring 311, which in some embodiments may maintain orselectively hold the jaw sets apart.

FIG. 16 is the section view of the clamp taken through the line 312-312according to one or more aspects of the present disclosure. In someembodiments, the inner jaw 341 may have a convex lower surface 345 thatfits against the saddle 342. An opening 344 in the inner jaw 341 may beconfigured such that the jaw set can be tilted relative to the shaft.The saddle 342 may include a relatively planar surface on a first sideand include a partially cylindrical depression or concavity on theopposing side. This may enable the jaw set 302 to pivot or tilt asdiscussed above. The opening 344 may be formed with a wider openingfacing toward the opposing jaw set 301, and a more narrow openingadjacent the spacer 307 a and the outer jaw 306 a. The saddle 342 maymate with the inner jaw in a manner that allows the inner jaw, the outerjaw, and the sliding spacer to roll about an angle transverse to boththe axis of the fixation element carried by the inner jaw and the outerjaw and the axis of the fastener.

FIG. 17 shows the same clamp in a section perpendicular to the view inFIG. 16 according to one or more aspects of the present disclosure. InFIG. 17, the inner jaw 341 is shown in section through the profile. Invarious embodiments, the saddle 342 may have a pocket with side walls346 that maintain the relative rotation about the shaft between theinner jaw and the saddle while allowing the jaw set to tilt. The innerjaw also may have a first groove 353 and a second groove 354. The outerjaw 306 a may have a first groove 351 and a second groove 352. Together,in an exemplary embodiment, the first grooves 351 and 353 form a firstpassage 355, and the second grooves 352 and 354 form a second passage356.

In an exemplary embodiment, clamp 300 shows the embodiment jaw set 302joined to another embodiment jaw set 301. It is contemplated that thejaw set 302 could be joined to another device, such as, for example, amulti-pin clamp or a telescoping tube, to form a different configurationexternal fixation frame.

FIG. 18 shows another clamp 400 according to one or more aspects of thepresent disclosure. Some features are similar to or the same asdescribed with reference to the other embodiments, and will not bere-described here. In some embodiments, clamp 400 is made from oneembodiment jaw set 401 mated to another embodiment jaw set 402. Both jawsets may have washers 405, 405 a, outer jaws 406, 406 a, and spacers407, 407 a. In an exemplary embodiment, the first inner jaw 408 and thesecond inner jaw 409 may mate together at a ball and socket joint.

FIG. 19 shows a section view of the clamp 400 according to one or moreaspects of the present disclosure. In various embodiments, the jaw set401 may have a stud 414 that is threaded into the inner jaw 408. In anexemplary embodiment, when the nut 404 is tightened, the jaw set 401 islocked, but the ball joint may still be free to move if the other jawset 402 is still unlocked. In some embodiments, inner jaw 409 may have asocket 410 which mates against a ball 411 on inner jaw 408. A threadedshaft 412 may have a ball 413 that rests in the ball 411 of the innerjaw 408. The shaft 412 goes through the inner jaw 409, spacer 407 a andouter jaw 406 a. In an exemplary embodiment, when the nut 404 a isloose, the inner jaw 408 and the outer jaw are configured to pitch,roll, and yaw relative to a device comprising the ball 413. In anexemplary embodiment, when the nut 404 a is tightened, the jaw set 402locks and the ball joint locks as well.

FIG. 19 shows that the outer jaw 406 may have a first groove 421 and asecond groove 422. Similarly, the inner jaw 408 may have a third groove423 and a fourth groove 424. In some embodiments, when the jaw set 401is assembled, the first and third groove 421, 423 may combine to form afirst passage 425 to grip a fixation element, and the second and fourthgroove 422, 424 may combine to form a second passage 426 to grip adifferently sized fixation element. FIG. 19 shows a similar arrangementfor the jaw set 402. The outer jaw 406 a may have a first groove 421 aand a second groove 422 a. Similarly, the inner jaw 409 may have a thirdgroove 427 and a fourth groove 428. In various embodiments, when the jawset 402 is assembled, the first and third groove 421 a, 427 may combineto form a first passage 429 to grip a fixation element, and the secondand fourth groove 422 a, 428 may combine to form a second passage 430 togrip a differently sized fixation element.

In an exemplary embodiment, the clamp 400 shows one embodiment jaw set401 and another embodiment jaw set 402. It is contemplated to join jawset 401 to a different device, such as, for example, a telescoping tubeor a multi-pin clamp, as part of a different arrangement externalfixation frame. It is also contemplated to join jaw set 402 to adifferent device as part of a different arrangement external fixationframe.

FIG. 20 shows another clamp 500 according to one or more aspects of thepresent disclosure. Some features are similar to or the same asdescribed with reference to the other embodiments, and will not bere-described here. In some embodiments, clamp 500 is made from oneembodiment jaw set 501 mated to another embodiment jaw set 502. Thefirst jaw set 501 has an outer jaw 506, a spacer 507, and an inner jaw541. The inner jaw 541 mates with a swivel 542. The second jaw set 502has an outer jaw 509 and an inner jaw 508. The inner jaw 508 mates witha second swivel 545. In an exemplary embodiment, the first swivel 542and the second swivel 545 mate together and the two jaw sets are clampedtogether by the fastener 503, the nut 504, and a washer 505. In someimplementations, the first swivel 542 and the second swivel 545 may bereferred to as a coupling mechanism arranged to couple the two jaw setstogether. Other complete mechanisms are contemplated, including theother coupling mechanisms described herein.

FIG. 21 shows the same clamp as FIG. 20 from another perspective. Inthis figure, the jaw sets 501 502 are both in a neutral position. Inthis position, any fixation element inserted in either jaw set would bepositioned perpendicular to the fastener 503.

FIG. 22 shows the same clamp as FIG. 21 from the same perspective asFIG. 21. In this figure, the jaw sets 501 502 are shown in a swiveledposition. This allows any fixation element inserted into either jaw setto be in a non-perpendicular position to the fastener 503.

FIG. 23 shows a section view of the clamp 500 according to one or moreaspects of the present disclosure. The section view is taken throughline 561 of FIG. 21. In FIG. 23 the outer jaw 506 has a first groove 521and a second groove 522. Similarly, the inner jaw 541 may have a thirdgroove 523 and a fourth groove 524. In some embodiments, when the jawset 501 is assembled, the first and third groove 521, 523 may combine toform a first passage 525 to grip a fixation element, and the second andfourth groove 522, 524 may combine to form a second passage 526 to gripa differently sized fixation element. FIG. 23 also shows a similararrangement for the jaw set 502. The outer jaw 509 may have a firstgroove 527. Similarly, the inner jaw 508 may have a third groove 528. Invarious embodiments, when the jaw set 502 is assembled, the first andthird groove 527, 528 may combine to form a first passage 529 to grip afixation element. The jaw sets 501 502 are configured to mate withswivels. In jaw set 501, the inner jaw 541 has an inner concave surface510 which mates with the swivel outer convex surface 511. Similarly, injaw set 502 the inner jaw 508 has an inner concave surface made fromstraight lines 550 550 a which mates with the swivel outer convexsurface 551 551 a.

The inner concave surfaces of the inner jaws and the convex surfaces ofthe swivels are configured to allow the jaw sets to pivot about atransverse axis perpendicular to the longitudinal axis established bythe clamping fastener and perpendicular to the axis of the fixationelement. In this embodiment, the center of rotation of the jaw set islocated on the swivel component side of the interface between the innerjaw and the swivel component. This is different than the articulationshown in clamp 300 or the known conventional clamp in U.S. Pat. No.9,138,260, where the jaw set rotates on a saddle about an axis on thejaw set side of the saddle/inner jaw interface.

FIG. 24 is a section view of the clamp in FIG. 23 taken through the line562. The jaw sets are shown in the same neutral orientation as FIG. 21.Swivel 542 may have a convex surface having a radius 513 which mateswith the concave surface having a radius 512 of inner jaw 541. Convexradius 513 is a greater radius than convex radius 511. By having radius511 swept along radius 513, the convex surface of swivel 542 is a torus.The concave radius 512 is a greater radius than concave radius 510. Byhaving radius 510 swept along radius 512, the concave surface of innerjaw 541 is a torus. The inner jaw 541 mates and retains an orientationwith the swivel 542 because the toroidal shapes are similar, aligningthe axes of each torus. The two inner jaw radii 510 512 may also be thesame, such that the inner jaw concave surface is a sphere. The twoswivel radii 511 513 may also be the same, such that the swivel convexsurface is a sphere. In some aspects, the surface is formed of cones,such as two cones.

In FIG. 24, inner jaw 508 shows inner concave surface 552, while swivel545 shows outer surface 553. In the inner jaw 508, straight lines 550550 a are swept along a curve, creating a concave surface 552 withconical sides. On the swivel 545, straight lines 551 551 a are sweptalong a curve, creating a convex surface 553 with conical sides. Innerjaw 508 mates against swivel 545 on the conical surfaces. The conicalsurfaces maintain alignment of the inner jaw to the swivel whileallowing the jaw set to articulate about the swivel.

FIG. 25 shows a section view of the clamp 500 from the same orientationas in FIG. 24, but with the jaw sets 501 502 tilted relative to thefastener. The tilting of jaw set 501 is allowed to occur due to slot 544being larger than the shaft. In this embodiment, the slot 544 is largerin the desired direction of tilt than it is in the perpendiculardirection seen in FIG. 23. A similar slot 544 a is incorporated into jawset 502.

The nut 504 is tightened on the shaft 503, which brings the jaw sets 501502 and the swivels 542 545 together. Serrations 543 543 a on the swivelcomponents 542 545 can be incorporated to increase the locking strengthof the swivel to swivel interface over relying on pure friction. The jawsets 501 502 are pinched between the swivels 542 545 and the washers 505or the nut 504 and the head of the fastener 503, locking them inrotation as they are clamped onto fixation elements. In the embodimentshown, a single washer 505 is placed between the nut 504 and the outerjaw 509. The washer is intended to make for a smoother feel whentightening the nut, and to minimize marking on the outer jaw. The washercan be removed to reduce the number of components. The washer 505 couldhave a concave surface 515 on the side opposite the nut to increase thecontact area with the outer surface 514 of outer jaw 509. A washer witha concave surface could be used between the head of the shaft 503 andthe outer jaw 506 to increase the contact area. Increasing the contactarea may provide a smoother unlocked articulation and a decrease inscratching between the components, but it is not required for highlocking strength or general function of the articulating feature.

In an exemplary embodiment, the clamp 500 shows one embodiment jaw set501 and another embodiment jaw set 502. It is contemplated to have anembodiment where jaw set 501 is joined to another jaw set 501. It iscontemplated to join jaw set 501 to a different device, such as, forexample, a telescoping tube or a multi-pin clamp, as part of a differentarrangement external fixation frame. It is also contemplated to join jawset 502 to a different device such as, for example, a jaw set 101, atelescoping tube or a multi-pin clamp, as part of a differentarrangement external fixation frame.

The fixation clamps described herein may be sized and shaped to permitclamping on fixation elements of a variety of sizes. In someembodiments, a first end of the inner jaws and the outer jaws are sizedand shaped to hold a fixation element of a diameter between 10 and 13mm, and the second ends of the inner jaws and the outer jaws areconfigured to hold a fixation element of a diameter between 3 and 6.5mm. In some implementations, the first ends of the jaws are configuredto hold a fixation element of a diameter between 6 and 9 mm, and thesecond ends of the jaws are configured to hold a fixation element of adiameter between 3 and 5 mm. In yet other embodiments, the first ends ofthe jaws are configured to hold a fixation element of a diameter between4 and 6 mm, and the second ends of the jaws are configured to hold afixation element of a diameter between 2 and 4 mm. And in yet otherembodiments, the first ends of the jaws are configured to hold afixation element of a diameter of 11 mm, and the second ends of the jawsare configured to hold a fixation element of a diameter of 5 mm. Thesevalues are for example only, and other sizes are also contemplated.

To verify the performance improvement provided by the slider, gripstrength testing of fixation elements was conducted. The testingcompared prior art clamps according to FIGS. 1a and 1b with the clampsaccording to FIG. 3. Both the prior art clamps and the preferredembodiment clamps were made from titanium alloy. The grip strength ofthe clamps was compared when gripping 11 mm diameter carbon fiber bars,as well as when gripping 5 mm stainless steel pins. Axial grip testedthe strength of the clamp in holding the bar or pin from slipping alongits longitudinal direction. Torsion grip tested the resistance of theclamp from allowing the cylindrical element to rotate. The clamps wereall tightened to the same 10 N-m torque. FIG. 26 shows the relativeresults of the different tests. The difference in grip strength issignificant for all tests, with a big difference shown on the pin grip.

In all the previous descriptions, the elements have been shown ascylinders. Other external fixation elements, such as rings, square bars,rectangular bars, and hexagonal bars may all be used as framecomponents. It is contemplated that the jaw sets can be configured togrip any of these shapes and other frame component shapes of the like.

Persons of ordinary skill in the art will appreciate that theembodiments encompassed by the present disclosure are not limited to theparticular exemplary embodiments described above. In that regard,although illustrative embodiments have been shown and described, a widerange of modification, change, and substitution is contemplated in theforegoing disclosure. It is understood that such variations may be madeto the foregoing without departing from the scope of the presentdisclosure. Accordingly, it is appropriate that the appended claims beconstrued broadly and in a manner consistent with the presentdisclosure.

What is claimed is:
 1. An external fixation clamp configured to hold afixation element, comprising: a. an inner jaw with a first end shaped toengage a first size fixation element and a second end shaped to engage asecond size fixation element, b. an outer jaw with a first end shaped toengage the first size fixation element and a second end shaped to engagethe second size fixation element, c. a fastener configured to clamp theinner jaw and the outer jaw to at least one of the first and the secondfixation elements, the fastener having an axis, and d. a sliding spacerinterposed between the inner jaw and the outer jaw and being arranged toslide in a direction transverse to the axis of the fastener, e. thesliding spacer being structurally associated with the inner jaw and theouter jaw so that when the first size fixation element is introducedbetween the inner jaw and the outer jaw, the sliding spacer moves to afirst position where the sliding spacer and at least one of the innerjaw and the outer jaw are in contact at a first point away from thefastener, and when the second size fixation element is introducedbetween the inner jaw and the outer jaw, the sliding spacer moves to asecond position where the sliding spacer and at least one of the innerjaw and the outer jaw are in contact at a second point away from thefastener.
 2. The clamp of claim 1, wherein the outer jaw is configuredto tilt relative to the inner jaw to allow the fixation element to enterbetween the inner jaw and the outer jaw.
 3. The clamp of claim 1,wherein the first ends of the inner jaw and the outer jaw are configuredto hold a fixation element of a diameter between 10 and 13 mm, and thesecond ends of the inner jaw and the outer jaw are configured to hold afixation element of a diameter between 3 and 6.5 mm.
 4. The clamp ofclaim 1, wherein the first ends of the inner jaw and the outer jaw areconfigured to hold a fixation element of a diameter between 6 and 9 mm,and the second ends of the inner jaw and the outer jaw are configured tohold a fixation element of a diameter between 3 and 5 mm.
 5. The clampof claim 1, wherein the first ends of the inner jaw and the outer jaware configured to hold a fixation element of a diameter between 4 and 6mm, and the second ends of the inner jaw and the outer jaw areconfigured to hold a fixation element of a diameter between 2 and 4 mm.6. The clamp of claim 1, wherein the first ends of the inner jaw and theouter jaw are configured to hold a fixation element of a diameter of 11mm, and the second ends of the inner jaw and the outer jaw areconfigured to hold a fixation element of a diameter of 5 mm.
 7. Theclamp of claim 1, further comprising: a second inner jaw disposed alongthe axis relative to the first inner jaw; and a second outer jaw,wherein the second inner jaw and second outer jaw are disposed tocooperatively grip a second fixation element.
 8. A jaw set of anexternal fixation clamp, comprising: a. an inner jaw with a first endconfigured to engage a first fixation element and a second endconfigured to engage a second fixation element, b. an outer jaw with afirst end configured to engage the first fixation element and a secondend configured to engage the second fixation element, c. a fastenerconfigured to clamp the inner jaw and the outer jaw to one of the firstfixation element and the second fixation element, the fastener having anaxis, and d. a sliding spacer cooperatively engaging the inner jaw andthe outer jaw that can slide in a direction transverse to the axis ofthe fastener and transverse to an axis of said one of the first fixationelement and the second fixation element when said one of the firstfixation element and the second fixation element is disposed between theinner jaw and the outer jaw, e. wherein, when said one of the firstfixation element and the second fixation element is introduced betweenthe first end of the inner jaw and the first end of the outer jaw, thesliding spacer moves to a first position where the sliding spacer and atleast one of the inner jaw and the outer jaw are in contact at a firstlocation near the second end of the inner jaw or the outer jaw, andalternately when said one of the first fixation element and the secondfixation element is introduced between the second end of the inner jawand the outer jaw, the sliding spacer moves to a second position suchthat the sliding spacer and at least one of the inner jaw and the outerjaw are in contact at a second location near the first end of the innerjaw or the outer jaw.
 9. The jaw set of claim 8, wherein the first endof the inner jaw and the first end of the outer jaw form a first passageconfigured to hold the first fixation element of a first size and thesecond end of the inner jaw and the second end of the outer jaw form asecond passage configured to hold the second fixation element of asecond size different than the first size.
 10. The jaw set of claim 8,wherein the first end of the inner jaw and the first end of the outerjaw form a first passage configured to hold the first fixation elementwhen the first fixation element is a non-cylindrical element and thesecond end of the inner jaw and the second end of the outer jaw form asecond passage configured to hold the second fixation element when thesecond fixation element is a different shape than the non-cylindricalelement.
 11. The jaw set of claim 10, wherein the second end of theinner jaw and the second end of the outer jaw form are configured tohold the second fixation element when the second fixation element is acylindrical element.
 12. The jaw set of claim 10, wherein the second endof the inner jaw and the second end of the outer jaw form are configuredto hold the second fixation element when the second fixation element isproportionally the same shape as the first fixation element but adifferent size from the first fixation element.
 13. An external fixationclamp configured to grip a size-range of fixation elements, comprising:a. an inner jaw with a first end and a second end; b. an outer jaw witha first end and a second end, the first end of the inner jaw and thefirst end of the outer jaw being disposed to cooperatively form a firstpassage sized to grip a first fixation element having a first size, thesecond end of the inner jaw and the second end of the outer jaw beingdisposed to cooperatively form a second passage sized to grip a secondfixation element having a second size; c. a fastener configured to clampthe inner jaw and the outer jaw to at least one of the first and thesecond fixation elements, the fastener having an fastener axis; and d. aspacer slidingly moveable relative to the inner jaw and the outer jaw,the spacer being arranged to slide and intersect the second passage whenthe first fixation element having a first size is introduced to thefirst passage, the spacer being arranged to slide and intersect thefirst passage when the second fixation element having a second size isintroduced to the second passage.
 14. The external fixation clamp ofclaim 13, wherein the slider is slidingly interposed between the innerjaw in the outer jaw.
 15. An external fixation clamp configured to gripa size-range of fixation elements, comprising: a. an inner jaw with afirst end and a second end; b. an outer jaw with a first end and asecond end, the first end of the inner jaw and the first end of theouter jaw being disposed to cooperatively form a first passage sized togrip a first fixation element having a first size, the second end of theinner jaw and the second end of the outer jaw being disposed tocooperatively form a second passage sized to grip a second fixationelement having a second size; c. a fastener configured to clamp theinner jaw and the outer jaw to at least one of the first and the secondfixation elements, the fastener having a fastener axis, and d. a spacerslidingly moveable relative to the inner jaw and the outer jaw andslidable between the first and the second passages, the spacer engagingone of the inner jaw and the outer jaw at a first fulcrum point when thefirst fixation element having a first size is introduced to the firstpassage, the spacer engaging one of the inner jaw and the outer jaw at asecond fulcrum point when the second fixation element having a secondsize is introduced to the second passage, the first fulcrum point beingdisposed on a first lateral side of the fastener axis and the secondfulcrum point being disposed on a second different lateral side of thefastener axis.
 16. The external fixation clamp of claim 15, wherein theslider is slidingly interposed between the inner jaw and the outer jaw.